up there. >> absolutely. they're not going to let this event take away from the great event of the boston marathon. this is always going to be remembered, but we'll move -- we'll move ahead. >> okay. got to go. we got to go. dan shaughnessy, thank you. brent o'connor. we're going to come back. we're going to be back in an hour with the very latest of this investigation at 7:00 eastern. right now coverage continues with the reverend al sharpton. thanks, chris. and we start with the latest of the terror attacks at the boston marathon. three people are confirmed dead. at least 176 more are injured. some of them critically. with missing arms or legs. two of the dead have been identified. the first, 8-year-old martin richard. martin was in the third grade. his mother and sister were seriously wounded. this photo of him is breaking hearts across the country. martin holding up a sign that

says "no more hurting people, peace." the other identified victim is 29-year-old krystle campbell. her father says the family is shocked and devastated. officials think the bombs consisted of explosives and shrapnel packed in pressure cookers. hidden inside black duffel bags. president obama will travel to boston on thursday to speak at an interfaith service. today, he vowed to find those responsible and labeled the bombings an act of terrorism. >> this was a heinous and cowardly act. and given what we now know about what took place, the fbi is investigating it as an act of terrorism. any time bombs are used to target innocent civilians, it is an act of terror. it will take time to follow

every lead and determine what happened. but we will find out. we will find whoever harmed our citizens and we will bring them to justice. >> today we also are getting new video of the actual explosions. including the only tape we've seen taken by a woman actually running in the race. [ explosion ] . >> and new radio calls from first responders reveal the chaotic moments just after the explosions. >> we have reports of two explosions here. we have at least a dozen people with serious injuries. >> at least two explosions.

a dozen serious injuries, a multiple injury incident. >> authorities are now asking anyone with potential photo or video evidence to come forward and help the investigation. joining me now live from boston is mikeal isikoff, national investigative correspondent for nbc news. with me here in the studio is nbc news terrorism expert michael leiter. former director of the national counterterrorism center. thank you both for joining me. michael isikoff, let me go to you first. "the boston globe" is reporting that officials have recovered a second -- from the scene of the exploexs. what is your take on that? >> well, the fbi would not confirm that at the briefing we just had. they did confirm there are two devices, both in black nylon bags. search -- pressure cooker bombs.

one point that i thought was quite interesting that fbi special agent in charge deloria made, these are heavy bombs. two heavy bombs in black nylon bags at two locations about 75 to 100 yards away from each other that were set off within 12 seconds. it remains an open question whether that could have been done by one perpetrator or more than one to have placed those two bags within a short period of time in this open, crowded area and not be noticed. it does raise questions whether one person could have pulled that off. i should tell you that a couple of other pieces of information i've learned tonight that federal law enforcement source confirms that prosecutors are preparing search warrants. most likely to be executed tomorrow. a limited number in the boston area in their continuous search for evidence in this case. that suggests that there are at

least some leads, but mr. deloria made clear the investigation is in its infancy, and the number of -- the search for suspects and motives remains wide open. >> leiter, what does this mean? i mean, is there anything here that's a breakthrough? the public clearly wants to see what happened and why, but at the same time, you don't want to rush and -- and bring in something or someone that you can't really get the evidence to back up. so is there any breakthrough at all in any of this? >> well, it's still relatively early, but i think there are two things that are really important. the type of bomb doesn't tell us all that much. lots of different groups have used this bomb. you can find out how to make a pressure cooker bomb on the internet. >> wait a minute. you can find out how to make this bomb on the internet. so we don't -- we can't say this type of bomb tells us something about its group "a" that uses this or terrorist group "b" or

that it's foreign or domestic. none of that comes from our knowing the type of bomb. >> that's right. both domestic and international groups have used this kind of bomb. recently it was the type of bomb used by the pakistani taliban in times square which didn't work. one piece that is important that came out today, the fbi now knows how these bombs were delivered to the scene. at least in their final stages. that they were in black bags. and you've heard all the calls for the video and pictures from the public. this is critical because the fbi now knows a little bit more what to look for. they know what's suspicious. which is large or at least black duffel bags, carrying 40-pound weights. that is rather distinctive. and they can look for that in these videos. >> when they're looking through these videotapes and pictures, they know now what they're looking for. people carrying these black duffel bags, rather than just looking at random for something suspicious. >> that's right. otherwise just trying to figure out who's suspicious, not so easy.

knowing people are carrying black duffel bags, that's important. >> let me show you this. you and michael isikoff. fbi moments ago talking about what was recovered from the scene. let me show you this press conference. >> among items partially recovered are pieces of black nylon which could be from a backpack and what appeared to be fragments of bbs and nails, possibly contained in a pressure cooker device. this morning it was determined that both of the explosives were placed in a dark colored nylon bag or backpack. the bag would have been heavy because of the components believed to be in it. >> michael isikoff, that's the fbi agent in charge of the investigation. he's describing the bags as we've just heard leiter here talk about, michael leiter, and the significance of that. does that suggest to you, one, it helps them identify as michael has said what they can look for on the photo, but that it may lead toward what you're

saying, that some are saying this may have had to be more than one person? >> well, we don't know that. just picking up on -- on mike's point there, the significance of knowing you're looking for somebody carrying a black nylon bag, that does help explain these repeated requests to the public for cell phone videos or p pictures that might have been taken at the scene. not only that, they've gone so far, i.c.e. agents, immigrations custom enforcement agents, have been at logan airport today questioning travelers who are leaving the city, asking them if they had any such cell phone videos or pictures, which is an unusual tactic and length to go to to get those photographic images. in a lot of ways, they're looking for the zabruter film of this boston marathon bombing, zabruter being the individual who took the film of the john f. kennedy assassination.

>> now, leiter -- i'm calling you leiter because both of you are named michael. the fact that we are hearing now that the fbi and others are asking for pictures and videos, i understand about the nylon bags. but the fact that we know that this bomb, how it was made, i'm a new yorker. is that not the same way the bomb in the times square attempted bombing was made? wasn't it the same type of bomb? and does that tell us anything about the same type of people may be behind it or it doesn't mean anything? >> i don't think it means that much. it was the same kind of bomb as in times square. and that attack was sponsored by the pakistani taliban. >> okay. >> two reasons that's not that important. first of all, the pakistani taliban has already said they didn't do this. if they have, i think they would have taken credit for it. second, that was an exception for how groups like the pakistani taliban and al qaeda normally build bombs. >> oh, it was an exception? >> that's not what they've used in the past. >> okay. >> so i don't think that's a

tactic they would be likely to use. one last point that is important. we have to note. is the circuit board. that gives the fbi a sense of how the device might have been detonated and controlled. and also circuit boards can potentially be traced. if it's from a cell phone and the like, there might be a history about that cell phone. so that will be another critical investigative piece for the fbi and the boston police. >> michael isikoff, is it troubling or should we be troubled that there seems to be no leads or no theories that are being put out publicly yet a day later? or are we being overly anxious? i'm talking about the public. >> sure. and, look, there is a contradiction here. mr. deslaurias said yesterday there's no imminent physical threat to the public. but the fact is that there is a bomber, a terrorist bomber or bombers who are at loose in the community. and who they don't know who they are at this point.

so i think that is on its face a pretty troubling situation. and, you know, it does raise questions about just how calm and reassuring federal officials can be at this point. >> now, leiter, the doctor at boston hospital says that shrapnel is being removed from bomb victims. look at this. >> we have removed objects from at least three patients that clearly were designed to be projectiles and were built into the explosive device. these objects are ball bearing type or small shot type. we have also removed over a dozen small carpenter type nails from one patient. >> small type, carpenter type nails. does that tell us anything about the people or person that may have done this and what was used? >> it doesn't tell us anything about the people. what it does tell us is what they're trying to do. and they're not just trying to scare, they're trying to maim and kill. >> so this was intended to maim and kill.

this was not just something to scare people at a big event. >> i think there is no argument to the contrary. putting things like that, you are trying to get projectiles that are deadly to the people around them. >> all right. michael leiter and michael isikoff, thank you both for your time tonight. coming up, ordinary people reacting in an extraordinary way. stories of heroism and kindness in a moment of crisis. and we're learning more about the 8-year-old boy, martin richard, who died in yesterday's blast. and how his community is coming together for his family. [ male announcer ] you are a business pro.

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we're learning more about the victims tonight. 8-year-old martin richard, he was in the third grade. his mother and sister were seriously wounded.

the other identified victim is 29-year-old krystle campbell. we'll have more on them, next. the third deceased victim is a grad student at boston university. they have not released the same. more on all of that after this. n are proven to be effective pain relievers. tylenol works by blocking pain signals to your brain. bayer advanced aspirin blocks pain at the site. try the power of bayer advanced aspirin. that nasty odor coming from your washer. say farewell to the smell with tide washing machine cleaner. it goes straight to the source of the stink to lift odor-causing residues off your washer's drum. tide washing machine cleaner.

today we're learning the tragic, amazing personal stories of the survivors. americans who went out to watch a marathon on a sunny boston day and wound up having their lives changed forever in a matter of seconds. like these two brothers. there to watch a friend cross

the finish line. both brothers lost part of their legs. like these sisters, erica and nicole. there to watch their mother run the marathon. nicole had at least two surgeries to hold the bones together in her leg. erica remains in critical condition after having one leg amputated below the knee. these are just a few of the incredible stories of survival. but we're also learning more about those that didn't survive. 29-year-old krystle campbell of arlington, massachusetts, was among the dead. she was there cheering on her boyfriend. her devastated father talked about how she was always willing to lend a hand. and we're learning more about 8-year-old martin richard. friends and neighbors remember him as a boy full of life who loved sports, running and climbing the neighborhood trees. his mother, denise, a school librarian and his 6-year-old

sister, jane, were critically wounded in the attack. they are just a few of the mhumn stories of inspiration and tragedy that are capturing our hearts tonight. joining me now live from boston is msnbc's chris jansing, host of "jansing & co." i wanted to ask you because it really got to me about this 8-year-old boy. what more are we learning? >> the first pictures we saw of him was this kid with this megawatt smile and it broke your heart. then there was something else that came out, and it really has moved people so deeply. it was a photo taken less than a year ago. and the school that he went to was having a peace march. and he had made a sign. it had just four simple words on it. no more hurting people. and then a peace sign. and to think that he was the

victim of violence. he was there at the finish line with his family. they had gone together to have a great day. apparently he had just come back from getting some ice cream. and when the blast happened, he was killed. his mother had to have surgery. she has a serious brain injury. and his sister, who is just a first grader at the same school where their mother was the librarian, has had one of her legs amputated. the school released a statement about young martin richard, calling him a bright, energetic young boy who had big dreams and high hopes for his future. we are heartbroken by this loss. and so many of the neighbors, the father was a community organizer and beloved in the community. they've been going to the home and leaving flowers and leaving balloons and leaving candles. it is hard to put into words what that neighborhood is feeling or the entire community about what's happened to this family, rev. >> any death and all three

certainly have shaken everyone. but when i saw that photo of him in the peace walk less than a year ago, it really just stood out. but we're also learning more about krystle campbell, who lost her life yesterday. what are you hearing about her? >> she was a restaurant manager. she was 2001 graduate of a local high school, medford high. she had gone like so many people -- the thing about the boston marathon is that people go with their best friends. they go with their families. she had gone with her best friend to cheer on another friend who was running. there have been postings put up and websites dedicated to her. she's described as having a million dollar smile and gorgeous, bright red hair. and not surprisingly, her father has said the family is absolutely devastated by her loss, rev. of course, you can understand. >> oh, yeah. we certainly can. now, we briefly mentioned the story of two brothers, j.p. and paul nordin who each lost part

of a leg in the bombing yesterday. what dewe know about their story, chris? >> your heart stops when you hear what happened. their mother, liz nordin, was coming home from the grocery, and her phone rings. it's her son, and he says, ma, i'm hurt real bad. he was in an ambulance on the way to the hospital. he had somehow gotten separated from his brother. they're 33 and 31. they had gone to the race. again, you know, to have a good time. and they ended up in separate hospitals. and both of them have ended up having one of their legs amputated below the knee. and, in fact, as of this morning, doctors had not allowed their mother to visit because they were heavily sedated. and she said -- told some local reporters that she was absolutely dreading going in there and having to see them. hard to believe that in one family, again, something like this could happen, rev. >> wow. well, chris jansing, thank you

for your time tonight. >> thank you. boston is an important city. it's where america's freedom was borne e born. the boston tea party happened there. the single act of defiance that told the british rulers, no more. the shot heard round the world that started the american revolution was fired there. it led to the signing of the declaration of independence. these were the original minutemen. the first acts of bravery that formed the nation happened there in boston. this is not the kind of city that gives up easily. the mayor talked about that. >> a lot of people willing to work together to make this a better place for all our people. and so as we gather here today with all our officials, let's say boston will overcome. >> my trips to boston, and i've been there often, the people are proud. the people have a real sense of

pride in the city. and they're resilient. they bounce back. they keep coming. and in this city, in this city that has so much history, that has shown so much of where this nation was actually born and emerged from, this is the city that we're looking at tonight with this horrific act. joining me now is "boston globe" columnist kevin cullen. kevin penned a very moving piece about yesterday's event. he wrote, quote, in an instant a perfect day had morphed into something vis viscerally evil. we will get through this, but we will never be the same. thank you for your time. such tragedy in your city, kevin. you were walking around today. how is the city responding? >> well, al, i think you just used the right word.

it's a resilient city. it's also a tough city. i think you know that. we -- in boston we'll take two punches to land one. and whoever did this to us, they didn't just do it to us. they did it to everybody. but it's going to take a lot more than that. we're not going anywhere. and i will guarantee you, al, next year, the boston marathon will have a record field. people will come from all over the world as they do every year. but more people will come. and we will show the people who did this what they -- what they bit off. because they can't chew it. >> the -- the 8-year-old young man, young boy, who was killed, what can you tell us? i mean, people all over the world are looking at that photo of him saying, no more -- no more hurting people, peace. and it's captured the attention

of the world. he's one of the three victims. what can you tell us? >> well, all i can tell you is that martin represents everything that's good about this place. i didn't know him. i didn't meet him. i know his family's reputation. they're a great family. good dorchester people. and, you know, i was so struck that -- thinking that whoever did this, i wonder if they have children of their own or if they will some day have children of their own. and if that child says to them, hey, daddy, what did you do in the war? if that person answers honestly, they'd have to say, i killed an 8-year-old boy. his name was martin richard. that's what i did in the war. >> wow. let me ask you this, kevin. as you moved around there today and as you looked and talked to the people, do you get a sense

of fear or do you get a sense of we're going to come back, we're going to fight back, we're going to show the world the resilience that bostonians pride themselves in? >> i sense no fear whatsoever. i sense resolve. i sense people -- you know, al, the funny thing is, we are famously aloof here. i mean, you go to fenway park, you sit next to somebody, they wouldn't even talk to you. they wouldn't tell you what time it is. we are just that way. we're not -- people in chicago, they'll talk to a telephone pole. we're just different here. but i'll tell you, this is a great place. and there is a solidarity. i've been saying, i was in -- in omar, northern ireland in 1998 when a bomb exploded there and killed 28 people and an unborn child. i was in london in 2005, the 77 bombings where more than 50 people were killed by bombs on the underground and the bus there. and today felt like that. it felt -- there's incredible

sadness here. and we have to bury our dead. and we have to honor our first responders and make sure they're okay. but i'll tell you what, this place is focused. and we will get through this. and i say we will be -- we will never be the same, we'll be better. we'll be better. >> wow. i'm going to leave it right on that hopeful note. kevin cullen, thank you for your time. >> thanks, al. coming up, the intense effort to find out who committed these crimes, and the incredible stories of people who rushed to help others in those moments of fire and panic. the heroes of boston. stay with us.

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the world is responding to yesterday's tragedy in boston. across the globe, security immediately increased in major cities. today's world newspapers captured the emotion, too. a brazilian paper called it marathon of terror. in ireland, marathon mayhem. "the times" of london called it carnage. with this photo of the blast. london's marathon is this weekend, and it will go on as scheduled. now with a planned tribute to the boston bombing victims. this was the scene earlier today at the u.s. embassy in russia.

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are you still sleeping? just wanted to check and make sure that we were on schedule. the first technology of its kind... mom and dad, i have great news. is now providing answers families need. siemens. answers. welcome back. it's just past 6:30 p.m. eastern. here's the latest on the terror attacks in boston that have left three people dead and more than 170 hurt. president obama will travel to boston on thursday to speak at an interfaith service for the victims. we're learning more about the three dead victims.

one was 8-year-old martin richard. 29-year-old krystle campbell has also been identified. the third was a grad student at boston university. that name has not been released. investigators say the bombs were made from pressure cookers that were hidden inside duffel bags. as we struggle to make sense of what happened, today president obama reminded us of the best we've seen in boston. >> the american people refuse to be terrorized. because what the world saw yesterday in the aftermath of the explosions were stories of heroism and kindness and generosity and love. exhausted runners who kept running to the nearest hospital to give blood. and those who stayed to tend to the wounded. some tearing off their own clothes to make tourniquets. the first responders who ran into the chaos to save lives. the men and women who are still

treating the wounded at some of the best hospitals in the world. and the medical students who hurried to help, saying when we heard, we all came in. the priests who opened their churches and ministered to the hurt and the fearful. and the good people of boston who opened their homes to the victims of this attack and those shaken by it. >> stories of heroism and kindness of ordinary people reacting in extraordinary ways. like the doctor at massachusetts general hospital who rushed to get back to work. >> one of our physicians was actually running the marathon. and dehydrated as he was, he came back immediately after he finished the marathon to offer his help. >> he came straight from running the marathon to help victims at the hospital. we've also heard the story of former new england patriots offensive lineman, joe andruzzi. springing into action. >> the patriots have tweeted

this photo of andruzzi carrying a runner in the aftermath of the explosions. those explosions happening at the time when many of those running were doing so for charity, including andruzzi's charity. >> andruzzi has been a symbol of hope before. his three brothers were new york city firefighters during september 11th. and joined the patriots for the first football game after the 9/11 attacks. and here's the image that a lot of people are talking about today. carlos arredondo rushing to help an injured man to an ambulance. video taken immediately after the explosions show him leaping into action, trying to help the victims. at the height of danger, this man did what so many others did. he put his personal safety aside to help others. >> run across by the american -- by the flags. and start picking up people and bringing them to the emergency room here. >> you've been cut.

you're covered with blood. >> i was carrying somebody who lost both of their legs in the explosion. it was -- a lot of them lost limbs. catastrophic. i was carrying this flag. and i just -- my instinct was to go help and see what i can do. and let's just -- let's just pray for the angels. >> his instinct was to help others to see what he could do. and to pray. his sto it's stories like this that really give me hope. joining me now is danielle dinas, a doctor who had finished running the marathon when the bomb had gone off. she was actually receiving medical attention after the race, but sprang into action to help others. danielle, thank you so much for joining me. >> thank you. >> what did you actually do in the medical tent? >> i was actually in there getting treatment for myself when the bombs went off.

so i turned to the nurse who was working on me and i told her, look, if that was actually something real, i don't know what that noise was, but whatever it was, i'm a physician and i want to stay and help. please just tell me what i can do to help. i ended up helping set up a lot of iv lines, putting together kits for ivs, moving around cots to triage different patients into different areas depending on how severely they were injured. figuring out -- trying to help decide which patients needed to go to the ambulances and get to the hospital first and which ones could stay and wait a little bit longer. and then helping to discharge some of the runners who'd been in the tent before all this even started who just were there for leg cramps and whatever and wanted to get out and go find their families. >> so you had run. because i want people to understand this kind of -- of reaction that i think is heroic that you and others demonstrated. you had actually ran the entire race. was getting medical attention. and heard the blast and said, if

this is something wrong, i want to stay and help. this is after running 26 miles and hearing a blast that you didn't know what it could have been. rather than run, you could have run for safety, run for cover, you said, no, i'm going to stay here tired and help my fellow americans. >> yeah, i -- i really didn't see that there was an option for me. i knew that i could leave, but at the same time, i have the training and i have the ability to help in some way. and i think whenever you're in a situation like that, you have to ask yourself if you're going to be a help or a hindrance. i felt like i could be a help so i wanted to stay and do whatever i could. >> did it ever occur to you even for a fleeting second that you may be in danger, that you might be putting yourself in the line of some serious peril? >> it did cross my mind. they started rearranging things in the tent before they started bringing the first victims in, i

thought, you know, there could be another backpack in this tent and i would have no idea about it. but at the same time, you have no idea that there would be something on the street as soon as you walked out there, either. so i didn't feel like i was in any worse or better danger by leaving or staying. i figured i could do the most good by staying there. >> now, when you started seeing some of the victims come in, were any of them seriously injured that was in the particular tent that you were at? i mean, what did you see in terms of the victims that were brought in or the injured that were brought in? >> there were some pretty horrific injuries. anything from just minor cuts and scrapes all the way up to people who had lost part of their limbs or had clothing and shoes blown off. it was pretty horrible. >> and at that point, obviously, you knew it had been a bomb or something like that. and you just -- your medical side took over to help people. i would imagine some of them in

intense pain. >> yeah. we had actually had a disaster training preparedness day at our medical school as part of our fourth year of training right before we graduated. so i at least understood the flow of things and had seen some of the ways that they used to triage patients and kind of understood what was going on. so it gave me an idea of where i could step in to help. >> how long did it take you to run the marathon? >> it took me 3 hours and 13 minutes. >> after 3 hours and 13 minutes in the tent getting a little attention yourself, you stayed there and helped. you know, danielle, heroes are not those that would say, i was not afraid and i never had a second thought about danger. heroes are those that say, you know, this could be dangerous, but i'm going to do it any how. you are a hero in my book and thank you for being with us tonight. >> thank you so much. >> our next guest was at the

finish line of the marathon and shot stunning video just after the explosion. it's video you may not have seen yet. let's take a look. >> that's video from just after the bombs went off. joining me now is stamatis

ostra. the man who took that video. thank you for joining us tonight. your video really shows people jumping into action. how quickly were people starting to help one another? >> immediately. it was unbelievable. everybody jumped into someone in need. there were little babies that were in trouble. there were people covered in blood. we are not trained, we are not first responders, but immediately everybody who could help just jumped and helped each other. it was -- it was just everybody jumped in. >> so in a split second, when you hear the explosion, the bombs go off, there's this -- this chaos, bloodshed, broke limbs, and at the same time, people just spontaneously jumping in, that's what you saw? >> the first bomb went off and there was a little bit of stop.

and when the second one, like, 12 seconds went off, everybody knew there was something really wrong. and everybody jumped in. we -- we threw the rail down. we walked into the street. and there were people with blood that couldn't walk. there was a husband and a wife. he was begging to be close to his wife. a couple of guys and myself, we grabbed him, we put them together. we got them into the ambulances as fast as we could. it was terribly careless, but we did the best we could. >> all right, mr. astra, thank you for your time. >> thank you. ahead, new details about the investigation. stay with us. [ female announcer ] switch to swiffer 360 duster extender, and you'll dump your old duster. swiffer 360 duster extender cleans high and low, with thick all around fibers that attract and lock up to two times more dust than a feather duster. swiffer gives cleaning a whole new meaning.

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the person who did this is someone's friend, neighbor, co-worker or relative. we are asking anyone who may have heard someone speak about the marathon or the date of april 15th in any way that indicated that he or she may target the event to call us. someone knows who did this. >> the fbi agent in charge of

the investigation in boston saying the public will be crucial in finding those responsible. the fbi is examining photos like this. given to nbc affiliate whdh. to see if the nylon bags might have been placed in trash bags on the sidewalk to appear less conspicuous. now, we don't know if this particular bag is relevant. but it's one of many possible leads for investigators. joining me now is former fbi profiler, clint van zandt. clint, thanks for being here. >> good to be with you, al. >> what kind of information can we learn from photos like this? >> well, one of the things that the fbi will do is they'll take photographs of the actual blast area. they'll superimpose it over a photograph like you just showed us to try to suggest, did that blast actually originate from that bag or was it left, right

or behind it? so we've got -- we've got a baseline of where the explosion took place. any other photographs will be compared against those two explosion sites, number one, to see if a bag had been there. number two, we'll be looking for someone who carried such a bag. remember, al, that the fbi describes two different black nylon bags. if you think about -- if you think about these pressure cookers, a friend of mine, larry johnson, former cia, commented that these would weigh about 20 pounds each. that's a lot of weight for somebody to carry in that area, al. >> now, what kind of damage can these type of bombs do, these pressure cooker bombs? >> well, let's say, for example, in february of this year, a pressure cooker bomb was used in india, with us set off. 17 dead, 120 injured. in july 1976, a hijacking took

place in america. croatian separatists hijacked a new york to chicago flight. during the hijacking they said, and if you don't believe we have a bomb, look in a storage locker at grand central and you'll see a pressure cooker bomb. new york pd found it, took it out, tried to render it safe. the thing exploded and killed a bomb tech. so these can be very deadly. and, al, these things have been used for 30, 40 years in afghanistan, pakistan and other places like this. >> now, does this suggest, then, i'm going to ask you -- i asked an earlier guest, does this suggest a certain type of group or certain type of -- of ideological thinking body uses this type of weapon or type of bombs, or is this just used by

different types in different places and occasions that you've already named for us? >> well, al, a similar -- once again, a similar type twice was contained inside the vehicle in 2010 that a former pakistani national set in times square, tried to detonate to blow up in times square. so here we have one used by creatikre crowuation terrorists, one used by pakistanis and one in india. all of these by definition have one thing in common. they have more of an international aspect to them than they do a domestic. that's just part of the investigation. part of the consideration the fbi and the joint terrorism task force has to have as they try to understand the origin of this device and whose hands put this monstrous device together. >> now, does that, then, suggest that the bomber or bombers had

ties to some overseas group? >> well, you know, it used to be, al, you had to get on a plane and go to some terrorist training camp and learn how to build these things. now you go on the internet. you go into certain websites and it has all of the plans, all of the making, everything you want to. so there are terrorist training camps right now being conducted on the internet that's in front of every american. so while that may have one time had a purely international connotation, now we could still get a hybrid, al. you could get an american, for example, who was somehow radicalized who got on those websites, learned how to build that device, and set it off for a to be determined political, religious or personal reason to commit the mayhem that he did. >> clint van zandt, thank you

for your time. >> thank you, al. how americans come together in the face of unspeakable tragedy. that's next. i don't like to golf. i love to golf. ♪ [ grunts ] yowza! that's why i eat belvita at breakfast. it's made with delicious ingredients and carefully baked to release steady energy that lasts... we are golfing now, buddy! [ grunts ] ...all morning long. i got it! for the win!

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♪ it's not rocket science. it's just common sense. from td ameritrade. as i was traveling today coming through the airport, a lady said to me, reverend al, what to i say to my grandchildren about how heinous some group could be? i said to her say to them how loving, how caring, how heroic of this world, of people who ran the race didn't turn around for shelter when they heard the bomb. they ran in danger's way to stand up for other citizens. say to them how people ran into the smoke, not knowing if another bomb would go off. how people interrupted their own lives and safety to try and shield others. what makes this